Prøv at angive en bredde af tabellen gennem css.
<table border="1" style="table-layout: fixed; width: 150px;">
<tr>
<th>Id</th>
<th style="word-wrap: break-word;">numbers</th>
</tr>
<?php while( $row = $stmt->fetch(PDO::FETCH_ASSOC) ) { ?>
<tr>
<td style="word-wrap: break-word;"><?php echo $row['id']; ?></td>
<td style="word-wrap: break-word;"><?php echo $row['numbers']; ?></td>
</tr>
<?php } ?>
</table>